How to Put In the Right Footing for Deck

LESLIE: Shane in Illinois, you’ve got The Money Pit. You want us to help you with a footing for deck? What can we do?

SHANE: As respect to a footing for deck, is it more common practice to have a one solid column that goes down for your footing or can you just dig 36 inches, throw a 6-inch footing at the bottom of that and put your post on top of that and just pack it around with dirt versus covering it with concrete?

TOM: You mean covering the post, like around – pouring around the post with concrete? Is that what you’re saying?

SHANE: Correct.

TOM: Yeah. Well, that wouldn’t really help you because that’s not giving you any support. The idea of the footing for deck is to get it down below the frost line. So yes, if you dug down to 36 inches and you set any kind of a small concrete pad for the deck post, you would be fine by putting the footing – putting the post on top of that and going up.

Now, the other thing that you could think about doing – and I like these – there are precast footings that are out there that are kind of like almost pyramid shape. They’re very tall. Not a pyramid, more like a tower. And they’re about 36 inches tall, maybe 40 inches tall. And they have a bolt that sticks out the top of them so you can put your post on right on that. And you can dig your hole and drop this right into the hole.

What I like to do is put maybe a shovel full of stone at the bottom of the hole, make sure it’s tamped really well and then drop my footing on top of that. And this way, my post ends up above grade. I don’t like the idea, even though it’s pressure-treated, of sinking the wood in the ground.

SHANE: Yeah, I agree.

TOM: Because eventually, it’s going to rot. So, I like to keep it above ground. That’s why I use those types of posts.

And then the third way you could do this is with something called a Sonotube. You know what that is?

SHANE: Yeah.

TOM: Yeah, it’s like – it looks like a paper-towel roll but it’s 12 inches in diameter. And yeah, you cut that to be about 40 inches, set that in the hole. You can go ahead and backfill around it, put a little stone in the bottom and then fill it up with concrete.

Now, you could mix up – something like QUIKRETE in the red bag is good for this. You can mix it up and drop it into that Sonotube. It’ll be hard inside of an hour. And you could start building right away.

SHANE: Well, great. Well, thank you for your help.

TOM: Yeah, you’re welcome. Good luck with that footing on deck project. Are you going to get it done and soon enough to enjoy it this summer?

SHANE: Possibly. We’ll see.